Genetic structure and population differentiation of endangered Scrophularia takesimensis (Scrophulariaceae) in Ulleung Island, Korea

2011 ◽  
Vol 41 (3) ◽  
pp. 182-193 ◽  
Author(s):  
Sun Mi Ma ◽  
Yong Seok Lim ◽  
Sung Tae Na ◽  
Jun Lee ◽  
Hyun Chur Shin
Keyword(s):  
Genetic Structure ◽  
Population Differentiation ◽  
Ulleung Island

scholarly journals Spatial Genetic Structure within Populations of Sorbus torminalis (L.) Crantz: Comparative Analysis of the Self-incompatibility Locus and Nuclear Microsatellites

2016 ◽  
Vol 58 (1) ◽  
pp. 7-17 ◽  
Author(s):  
Sandra Jankowska-Wroblewska ◽  
Joanna Warmbier ◽  
Jaroslaw Burczyk
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Population Differentiation ◽  
Spatial Genetic Structure ◽  
Population History ◽  
The Self ◽  
Nuclear Microsatellites ◽  
Self Incompatibility ◽  
Sorbus Torminalis ◽  
Incompatibility Locus

AbstractDistribution of genetic diversity among and within plant populations may depend on the mating system and the mechanisms underlying the efficiency of pollen and seed dispersal. In self-incompatible species, negative frequency-dependent selection acting on the self-incompatibility locus is expected to decrease intensity of spatial genetic structure (SGS) and to reduce population differentiation. We investigated two populations (peripheral and more central) of wild service tree (Sorbus torminalis(L.) Crantz), a self-incompatible, scattered tree species to test the differences in population differentiation and spatial genetic structure assessed at the self-incompatibility locus and neutral nuclear microsatellites. Although, both populations exhibited similar levels of genetic diversity regardless of the marker type, significant differentiation was noticed. Differences betweenFSTandRSTsuggested that in the case of microsatellites both mutations and drift were responsible for the observed differentiation level, but in the case of theS-RNaselocus drift played a major role. Microsatellites indicated a similar and significant level of spatial genetic structure in both populations; however, at theS-RNaselocus significant spatial genetic structure was found only in the fragmented population located at the north-eastern species range limits. Differences in SGS between the populations detected at the self-incompatibility locus were attributed mainly to the differences in fragmentation and population history.

scholarly journals Genetic Diversity and Population Differentiation of the Causal Agent of Citrus Black Spot in Brazil

2012 ◽  
Vol 2012 ◽  
pp. 1-14 ◽  
Author(s):  
Ester Wickert ◽  
Antonio de Goes ◽  
Andressa de Souza ◽  
Eliana Gertrudes de Macedo Lemos
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Population Differentiation ◽  
Sweet Orange ◽  
Black Spot ◽  
Pathogenic Fungi ◽  
Its2 Region ◽  
Citrus Black Spot ◽  
Different Populations ◽  
Different Origins

One of the most important diseases that affect sweet orange orchards in Brazil is the Citrus Black Spot that is caused by the fungusGuignardia citricarpa. This disease causes irreparable losses due to the premature falling of fruit, as well as its severe effects on the epidermis of ripe fruit that renders them unacceptable at the fresh fruit markets. Despite the fact that the fungus and the disease are well studied, little is known about the genetic diversity and the structure of the fungi populations in Brazilian orchards. The objective of this work was study the genetic diversity and population differentiation ofG. citricarpaassociated with four sweet orange varieties in two geographic locations using DNA sequence of ITS1-5.8S-ITS2 region from fungi isolates. We observed that different populations are closely related and present little genetic structure according to varieties and geographic places with the highest genetic diversity distributed among isolates of the same populations. The same haplotypes were sampled in different populations from the same and different orange varieties and from similar and different origins. If new and pathogenic fungi would become resistant to fungicides, the observed genetic structure could rapidly spread this new form from one population to others.

scholarly journals Population Genetic Structure of Septoria passerinii in Northern Great Plains Barley

2007 ◽  
Vol 97 (8) ◽  
pp. 938-944 ◽  
Author(s):  
S. H. Lee ◽  
S. M. Neate
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
North Dakota ◽  
Population Genetic Structure ◽  
Population Differentiation ◽  
Population Genetic ◽  
Genotypic Diversity ◽  
Aflp Markers ◽  
Northern Great Plains ◽  
Geographical Regions

The genetic structure of Septoria passerinii from nine field populations was examined at several scales (within lesions, among lesions in a leaf, among leaves in a field, and among fields in North Dakota and western Minnesota) by using amplified fragment length polymorphism (AFLP) markers. A total of 390 isolates were sampled from seven barley fields located in North Dakota and two barley fields located nearby in western Minnesota in 2003 and 2004. Based on 57 polymorphic AFLP markers, AFLP DNA fingerprints identified 176 different genotypes among 390 (non-clone-corrected) isolates in nine different fields. In two intensively sampled sites, ND16 (Williston, ND) and ND17 (Langdon, ND), only one to four different genotypes were found within a lesion. A higher level of genetic and genotypic diversity was found within a leaf in which six to nine different genotypes were found from lesions on a leaf. The genetic diversity within a leaf was similar to the genetic diversity within a field. The average genetic diversity (H) within a field across all AFLP loci was approximately 0.3, except at site ND12 (Carrington, ND) where it was 0.16. Genotypic diversity was high in all populations, and with the exception of ND15 (Rothsay, MN), very low multilocus linkage disequilibrium values ( rd) were found in all populations. The population differentiation, GST, was relatively high (GST = 0.238) among the nine populations due to the high GST in ND12, ND14 (Twin Valley, MN), and ND15. Population differentiation without those three populations was 0.09. A lack of correlation between geographical distance and genetic distance was found, suggesting the potential for a high level of gene flow between different geographical regions. The population genetic structure described in this study for S. passerinii in North Dakota and western Minnesota is consistent with that of a sexually reproducing fungus.

History, selection, drift, and gene flow: complex differentiation in checkerspot butterflies

1990 ◽  
Vol 68 (9) ◽  
pp. 1967-1975 ◽  
Author(s):  
John F. Baughman ◽  
Peter F. Brussard ◽  
Paul R. Ehrlich ◽  
Dennis D. Murphy
Keyword(s):  
Gene Flow ◽  
Genetic Structure ◽  
Population Differentiation ◽  
Gel Electrophoresis ◽  
Low Level ◽  
Euphydryas Editha ◽  
Parallel Selection ◽  
Checkerspot Butterflies ◽  
Continuous Range

The genetic structure of the checkerspot butterfly, Euphydryas editha, was investigated using gel electrophoresis at 19 loci in each of 41 populations from throughout the range of the species. With two exceptions the populations were found to be very similar genetically, despite great differences in morphology and ecology. The low level of population differentiation was attributed to a combination of a historically more continuous range, parallel selection, and gene flow.

scholarly journals Reduced Global Genetic Differentiation of Exploited Marine Fish Species

2020 ◽  
Author(s):  
Miguel Gandra ◽  
Jorge Assis ◽  
Manuel Ramos Martins ◽  
David Abecasis
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Genetic Differentiation ◽  
Marine Fish ◽  
Fish Species ◽  
Population Differentiation ◽  
Environmental Changes ◽  
Meta Analysis ◽  
Genetic Connectivity

Abstract Knowledge on genetic structure is key to understand species connectivity patterns and to define the spatiotemporal scales over which conservation management plans should be designed and implemented. The distribution of genetic diversity (within and among populations) greatly influences species ability to cope and adapt to environmental changes, ultimately determining their long-term resilience to ecological disturbances. Yet, the drivers shaping connectivity and structure in marine fish populations remain elusive, as are the effects of fishing activities on genetic subdivision. To investigate these questions, we conducted a meta-analysis and compiled genetic differentiation data (FST/ΦST estimates) for more than 170 fish species from over 200 published studies globally distributed. We modeled the effects of multiple life-history traits, distance metrics, and methodological factors on observed population differentiation indices and specifically tested whether any signal arising from different exposure to fishing exploitation could be detected. Although the myriad of variables shaping genetic structure makes it challenging to isolate the influence of single drivers, results showed a significant correlation between commercial importance and genetic structure, with widespread lower population differentiation in commercially exploited species. Moreover, models indicate that variables commonly used as proxy for connectivity, such as larval pelagic duration, might be insufficient, and suggest that deep-sea species may disperse further. Overall, these results contribute to the growing body of knowledge on marine genetic connectivity and suggest a potential effect of commercial fisheries on the homogenization of genetic diversity, highlighting the need for additional research focused on dispersal ecology to ensure long-term sustainability of exploited marine species.

Sign in / Sign up

Export Citation Format

Share Document